Most people have looked up into the night sky and seen the fleeting flashes of light that are known as meteors. These flashes are caused by small sand-sized particles that are debris from comets, which melt in the atmosphere and never reach the surface of Earth. Sometimes these flashes come in showers, such as the famous Perseid meteor shower, which occurs from July 23 to August 22 when Earth crosses the debris-strewn orbit of comet Swift-Tuttle.

Meteorites, on the other hand, are extraterrestrial material that have made it to Earth's surface and can weigh many tons. This material is not related to comets but rather to other astronomical bodies. Deceleration of meteorites begins high in the atmosphere where the surface of the incoming body heats up to incandescence causing melting and ablation and forming a (usually) black fusion crust on the exterior. Whether a meteoroid makes it to Earth's surface...